Shackle



Patented July 23, 1940 PATENT OFFICE snAcKLE William Stevenson,Blundellsands, Liverpool,

l England Application July 21, 1939, Serial No. 285,781

` Claims. (Cl. 59-86) This invention is for improvements in or relatingto shackles and is concerned with the type of shackle which is U-shapedand has holes or eyes in the ends of the jaws through which a closurepin or the like is passed, one end of the closure pin beingscrew-threaded to screw into a correu spondingly threaded eye in` theshackle so that the shackle is closed whenthis pin is `screwed home.

Shackles of the aforesaid type are often used for connecting ropes andchains in marine work. One difficulty which often arises in such work isthat the operator connecting up the coupling has to use both hands tobring the part which is attached to the shackle and the other part whichis to be located between the shackle jaws together so that time iswasted in manipulating the pin into alignment and engagement with theeyes. Another difculty which often arises with screw-threaded shacklepins is that the pins drop out during making and connection of acoupling and the threads become damaged.

One object of the invention is to provide a simple construction ofshackle and pin which will obviate the aforesaid diiculties.

Accordingly the present invention provides a shackle of the type abovedescrbed in which the closure pin is restrained when the shackle isopen, from completewithdrawal from the shackle eyes by an abutment onthe pin co-operating with a stop on the shackle. Preferably the abutmentis spaced apart from its cci-operating stop by an amount which permitsthe end of the pin to be retracted into that eye of the shackle which isremote from the end of the pin when the latter is in the closedposition.

According to a further feature of the invention there is provided ashackle of the type described wherein an abutment is located on the pinso that it lies against the interior face of one jaw (when the pin is inthe closed position) and wherein the interior face of the other jaw isrecessed towards its exterior face, the base oi the said recess forminga stop for the abutment, whereby the abutment may be accommodated in thesaid recess when the shackle is opened. Conveniently the abutment isspaced from the base of the recess by a distance which is substantiallyequal to the distance between the head of the pin and the start of thethread remote from such head. In the accompanying drawing which showsvarious forms of the invention by Way of example:

Figure 1 is a part-sectional elevation of a shackle with the closure pinin the closed posi- Figure 2 is a sectional elevation on the lin II-lIof Figure 1;

Figure 3 is a fragmentary detailed sectional elevation to an enlargedscale of the shackle pin adjacent the threaded end ofthe shank andshowing one method of constructing an abutment;

Figure 4 is a sectional elevation onthe line V-IV of Figure 3;

`Figure 5 is a view similar to Figure 3 but showing an alternativemethod of forming the abutment;

Figure 6` is a sectional elevation on the line VI--VI of Figure 5;

Figure 7 is a similar view to Figure 3 showing a further alternativeconstruction of the abut-` ment;

Figure 8 is a sectional elevation on the line VIII-VIII of Figure 7; I

Figure 9 is a part-sectional elevation of a shackle having one threadedeyelet hole and a correspondingly threaded pin;

Figure 10 is a fragmentary detailed sectional view of a modified form ofabutment on the pin; and

Figure 11 is a part-sectional view of the ends of the shackle jaws witha modied form of pin closing the jaws.

Figure 12 is a part-sectional view of a modied spring abutment.

The shackle shown in Figures 1 and 2 is of the common inverted U-form,the jaws IIJ of which have eyes I'I and I2 formed in the ends thereofand in alignment to receive a closure pin` I3.

The eyes II and I2 are of different internal diameters, and arescrew-threaded respectively at I4 and I5.

Theclosure pin I3 has one end` I6 screwthreaded to engage with the eye II, and the other end Il of larger diameter than the end I6 andscrew-threaded to engage with the corresponding threads I5 of the eyeI2. The end of the pin has a turning head I8 for screwing the pin homein the closed position. This type of shackle and pin `has the materialadvantage that by reason of the threaded engagement of the pin with boththe shackle eyes, the pin serves as a strut or a tie to prevent collapseor distention of the shackle jaws. Since, however, the pin has two setsof threads on it it is important to avoid damage to these threads by thedropping ofthe pin.

In order to prevent complete disengagement of the pin I3 from the jawsI0 an abutment I9 is provided on the pin adjacent the threaded portionI6 thereof, and this abutment lies against the inside lface o f oneshackle jaw when the pin is screwed home as shown in Figure 1.` The jawIll having the eye I2 is slotted at 2U on its interior face to receivethe abutment I9 when the shackle` pin is retracted from the closingposition, but the slot 20 is not carried through to the outer face ofthe jaw so that a stop 2I is formed by the base of the slot againstwhich the abutment I9 rests as the pin `is withdrawn so that the shacklepin cannot be disengaged from the shackle. Since, however, the jaws ofthe shackle must be left clear for the insertion of the part to whichthe shackle has to be connected the abutment I9 must'be as thin aspossible providing that it has the necessary strength to hold the weightof the shackle in the retracted position. Similarly the slot 2B iscarried through the shackle arm sufficiently far so that the stop ZI isonly strong enough to hold the shackle pin in the retracted position.From this it will be seen, as shown in chain-dotted lines in Figure 1,that when the shackle pin is retracted to open the jaws an almostnegligible projection of the end of the pin is present due to thecombined thicknesses of the abutment I9 and the stop 2l. The degree ofprojection of the end of the pin is dependent on the spacing'oi theabutment on the pin and the stop on the shackle (considered axially ofthe pin) being as nearly equal as possible to the distance between theturning head of the pin and the start of the `thread remote from suchturning head. The l width of the abutment iii and of the correspondingslot 2li (seeFigure 2) is maintained at a minimum consistent with theabutment and stop having suicient strength to carry the weight oi thepin, and by this arrangement a full bearing surface between the pin andthe shackle eyes is obtained.

Itv will be observed lthat the construction described does not weakenthe shackle to any extent but yields thevery material advantage that thev shackle pin when withdrawn to open the jaws cannot become disengagedfrom the eye-holes and fall out and the threads become damaged when, forexample, working at heights above the deck of a ship; similarly if theoperator has to hold the shackle attached to one part and another partto be located between the jaws ci the shackle, on turning the shackleround the pin will slide towards the closed position by gravity enablingthe manipulator to effect a coupling.

In Figures 3 and l the abutment IQ is formed by channelling the shank ofthe pin I3 adjacent the threads Il@ with a morticing tool and turningthe metal which has been channelled upwardly to form the abutment. Y

In Figures 5 andl 6 the abutment is formed by means of' a small angleiron countersunk at 22 in the shank I3 and spot-welded in position.

In Figures 7 and 8 the abutment is formed by tapping a hole 23 in theshank I3 and inserting a grub screw 24 with a` flattened projecting part25.

The modification shown in Figure 9 is applied to the common type ofshackle having a closure pin with one threaded end I6 engaging acorrespondingly threaded eye II, the shank 2E of the pin I3 being plainupto the turning head 27. The Aabutment I@ engages the stop 28 at theend of a slot 253 in the shackle jaw 3U.

In the detailed View comprising Figure l0 the abutment IQ is hinged at3l to a base plate 32 countersunk and spot-welded in a recess 33 in thepin I3( vA spring 34 biases the ab-utment I9 to its lupright position.This construction of pin and abutmentis used in conjunction with theshackle having slotted jaws shown in Figure 1. In'some classes of workin which shackles are used the shackle pin has to be threaded through aloop in, for example, the end of a rope to be` attached to the pin, andthis loop may be substantiallyequal to the diameter of the pin; thus topass the pin through the loop the abutment must be capable of foldingdown against its spring 34.

In Figure 11 the threaded end I 6 of the pin I3 incorporates one or morespring-pressed plungers 35 only one of which is shown in Figure 10. Thisspring-pressed plunger when released from the eye-hole II of the shacklejaw I forms an abutment which will engage in the recess 3S on the insidesurface of the eye-hole I2, thereby enabling the whole of the threadedend I6 to be housed within the eye-hole I2, and leaving the spacebetween the jaws IG entirely unobstructed.

In the modification illustrated in Figure l1 the retaining means of theshackle pin is not so positive as the retaining means illustrated inFigures 1 to 10, but the construction may be used where it is essentialto have the jaws entirely unobstructed.

In the modification illustrated in Figure 12 the abutment I9 comprises aleaf spring bent to form a retaining pawl, the tail of the spring 37being spot-welded in the recess adjacent the threads I6.

I claim:

1. A shackle comprising a U-shaped body part, the jaws of which haveeye-holes, at least one of which is internally threaded, a closure pinhaving a turning head and a screw-threaded end remote from the saidhead, an abutment located on the pin so that it lies against theinterior face of one jaw when the pin is in the closed position and arecess on the interior face of the other jaw the base of which recess isadjacent the exterior face of the said jaw and forms a stop for theabutment.

2. A shackle as claimed in claim l, wherein the base of the recess isspaced from the abutment by a distance, along the axis of the pin, whichis substantially equal to the distance between the head of the pin andthe start of the thread remote from said head.

3. A shackle comprising a bow-shaped body part the arms` of which haveeye-holes in alignment with one another, and at least one of the saideye-holes being internally threaded, a closure pin having a turning headand a screwthreaded portion at the end of the pin remote from the saidhead, a spring-pressed abutment on the pin adjacent the threaded endthereof, and a corresponding recess in the eye-hole adjacent the turninghead, when the pin is in the closed position, which recess receives thesaid springpressed abutment on withdrawal of the pin to restrain the pinfrom complete separation with the shackle body part.

4. A shackle as claimed in claim 1 and having an abutment-receivingrecess open to one eyehole, and a spring-pressed abutment on the pinadapted to engage in the said recess and hold the end of the pin withinthe eye-hole when the pin is withdrawn to open the shackle.

5. A shackle comprising a U-shaped body part the jaws of which haveeye-holes at least one of which is internally threaded, a closure `pinhaving a turning head, and a screw-threaded end remote from the saidhead, an abutment located adjacent the screw-threaded end of the pin andangularly movable towards and away from the axis of the pin, a yieldingdevice between the abutment and the pin and biasing the abutment to itsprojecting position, and a stop for the said abutment on the -shacklewhereby the -pin when the shackle is opened is restrained from completewithdrawal.

WM. STEVENSON.

